Consider the following:
1. Tea and Cold Drink
2. Coca Cola and Pepsi
3. Ink and Pen
The cross elasticity of demand for which among the above would be almost Zero?

[A] 1 only

[B] 1 & 2 Only

[C] 1 & 3 Only

[D] 1 & 3 Only

Answer: [D] 1 & 3 Only

The tea and cold drink are neither substitutes nor complimentary. For perfect substitutes cross elasticity is infinite, for substitutes cross elasticity is greater than zero, for complementary (Ink and Pen in this question), cross elasticity is almost zero.